Aircraft wheel and brake assembly



May 5, 1959 F. c. ALBRIGHT AIRCRAFT WHEEL AND BRAKE ASSEMBLY OriginalFiled Feb. 18. 1950 2 Sheets-Sheet 1 y 1959 F. C(ALBRIGHT 2,885,033

AIRCRAFT WHEEL AND BRAKE ASSEMBLY I 2 Sheets-Sheet 2 Original Filed Feb.'18. 1950 45 J0 6W 3 m T EW/V/MV 6415/7/6/77 Snow;

United 2,885,033 AIRCRAFT WHEEL AND BRAKE ASSEMBLY Franklin C. Albright,South Bend, Ind., assignor to Bendix Aviation Corporation, South Bend,lnd., a corporation of Delaware Continuation of abandoned applicationSerial No. 144,943, February 18, 1950. This application April 11, 1956,Serial No. 577,612

4 Claims. (Cl. 188-152) The present invention relates to an aircraftwheel and brake assembly having greater load carrying and brakingcapacities than the conventional assembly of the same outside physicaldimensions. This application is a continuation of my application SerialNo. 144,943, filed February 18, 1950 and now abandoned.

The object of the present invention is to provide a wheel and brakeassembly having narrower dimensions than a conventional assembly butcapable of delivering the same performance. In achieving this object,the assembly will have fewer parts, be more economical to produce, andbe lighter in weight than the conventional assembly.

The above object is attained by utilizing the wheel sides as parts ofthe brake, one side serving to house the hydraulic actuating mechanism,and referred to hereinafter as a carrier, and the other side serving asa reaction brake element against which the other brake elements arecompressed.

Other objects will become apparent as the description proceeds.

In the drawings:

Figure 1 is a partial side elevation of an embodiment of the presentinvention; and

Figure 2 is a sectional view taken substantially on section line 2--2 ofFigure 1.

Generally stated, the present invention is comprised of a wheel havingaxially spaced sides and a disc type brake contained for the most partbetween said sides, one of said sides embodying the hydraulic actuatorportion of the brake. With this arrangement, the other one of the sidesbecomes the reaction member of the brake while at the same time servingas a wheel support.

Referring now to the drawings, a stationary hollow axle 10, usuallyrigidly fastened to the lower extremity of an aircraft landing gearstrut, receives a pair of spaced, inwardly inclined roller bearings 12and 14 which rotatably support, respectively, wheel sides 16 and 18.Secured to the outer peripheries of these sides 16 and 18 is a rimportion 20 of any preferred design and shown in the drawings as beingadapted for track gear use. A hub nut 22 is threadedly received in theend of axle 10 to abut against the outer edge of bearing 14 and tothereby hold the wheel against right-hand movement. A radial flange 24is formed on the inner peripheral portion of side 18 to engage the otherside of bearing 14, thereby positively locating said bearing 14 and theside 18 in position with respect to axle 10. The other side 16 issimilarly provided with a radial flange 26 which bears against one sideof bearing 12 while the other side of this bearing engages a spacer ring28 prevented from leftward movement by a complementary shoulder 30 onaxle 10. The bearings and wheel sides are thus positively held in axialposition in proper spaced relation.

The carrier or side 18 is shown as being formed with a plurality ofcircumferentially-spaced cylinder bores 32 interconnected by means of aconduit or passage 34, these bores reciprocably receiving pistons 36having rubber or the like sealing rings 38 fitted thereto. Return springasice semblies generally indicated by reference numeral 39 are alsocarried in side 18 between bores 32 thus making the radial portions ofthis side between adjacent bores 32 and spring assemblies 39 spokesections which obviously serve to carry a proportionate share of theload imparted to axle 10. Other types of actuators could be used inplace of the spot type above described, one example being an annularactuator. However, in using this latter type of actuator it may benecessary to increase the axial thickness of the side 18 to prevent theload of the vehicle from squeezing the open end of the annular chambertogether thereby binding the piston against actuating movement. Variousexpedients are available to provide this additional support, and sincethis invention comprehends a much broader concept of novelty, theseexpedients will not be adverted to hereinafter.

The other side 16 has an axially inwardly protruding concentric threadedportion 40 upon which is received a ring nut 42 which serves to directlytake the thrust load of the brake for transmission to side 16 throughthe connecting threads 44. This nut 42 affords a convenient means ofadjusting the running clearance of the brake elements and may be rotatedby means of the pinion 46 journaled near the outer peripheries of sides16 and 18 to engage the gear teeth 48 in the nut 42. By rotating theshaft 50, pinion 46 is rotated causing corresponding movement of nut 42which is thereby shifted axially on the threads 44. A set screw 52 maybe used to retain shaft 50 against accidental rotation and to secureannulus 42 in axial position.

Moving now to the friction assembly of the brake, a plurality ofcircumferentially-spaced axially extending rotor keys 54 are secured byany suitable means to the inner peripheral surface of the rim 20;however, these keys may of course be fastened between the outerperipheral portions of sides 16 and 18 depending upon preferred designpractice. In the illustrated embodiment, screws 56 are utilized tofasten rotor keys 54 in place. A pair of annular brake elements orrotors 58 faced with suitable friction lining 60 have their outerperipheries notched to slidably engage keys 54 whereby said rotors willbe caused to rotate with the wheel while being shiftable axially. Apressure plate 62 faced on one side with friction lining 60 is likewiseformed for cooperative engagement with keys 54 and is disposed adjacentside 18 contiguous with the exposed ends of pistons 36. Thus by movingthese pistons 36 toward the left, the pressure plate 62 will becorrespondingly moved. Completing the rotary brake elements, an annularplate 64, similar in shape to pressure plate 62, has a lined surfacewhich faces inwardly with the other surface facing outwardly to abutagainst nut 42. It is conceivable that this element 64 could bedispensed with and the friction lining fastened directly to the annulus42. While friction lining has been described and illustrated, it is tobe understood that any type of rubbing surfaces may be used in lieuthereof without departing from the spirit of this invention.

In order to support the annular non-rotatable brake elements or stators66, a torque-absorbing annulus, or torque ring 68 is secured againstrotation on axle 10 by any suitable means and, as illustrated, by themating splines 70. The outer periphery of this torque ring 68 is formedwith axially extending keys, similar to the keys 54, which arecooperatively engaged by mating portions of the inner peripheries ofstators 66. Thus these stators may be shifted axially while being heldagainst rotation.

The stators 66, illustrated as being of the segmented 16 serves the dualfunction of the braking reaction mern '3 her, or backing plate and aload supporting section of the wheel.

Referring now to the return spring assemblies 39, it is seen that onlythe pressure plate 62 is urged to released position. Each assembly 39'comprises a pin 72 passing through aligned openings in the side 18 andpressure plate 62. The pin 72 has a head 74 accommodated in a recess 76surrounding the pressure plate opening whereby said pressure plate 62may be drawn toward the right by corresponding movement of the pin 72. Ahelical spring 78 is compressed in a socket 80 in side 18, around pin72, to bear against retainer 82 secured to the right-hand end of pin 72.The compressed load of spring 78 is thus acting to constantly urgepressure plate 62 to'the right and released'position. The fluid pressuresystem of the brake comprises a stationary conduit 84 centrally disposedin axle which is terminated at its right hand end in a swivel fittinggenerally indicated by reference numeral 86. This fitting 86 is utilizedto transfer fluid pressure from stationary conduit 84 to a main rotaryconduit 88 which communicates with conduit 34 in side 18. The fitting 86is of conventional design; therefore, it is not deemed necessary to givea detailed description thereof at this point.

A brief explanation of the operation of the described embodimentfollows. With the wheel rotating and the brakes released, pressure fluidis introduced into stationary conduit 84, which passes through swivelfitting 86, external conduit 88, conduit 34,and into the cylinders 32 toforce pistons 36 outwardly against pressure plate 62. The rotors andstators are thereby compressed against the lining of element 64 togenerate the desired braking torque.

In releasing the brakes, the pressure in conduit 84 is relievedsufficiently to allow return spring assemblies 39 to shift pressureplate 62 to the right and released position.

In order to exemplify how the present invention accomplishes the earliermentioned objects, reference is hereby made to Du Bois applicationsSerial Nos. 71,891 (now Patent No. 2,551,253, dated May 1, 1951) and647,781 (now Patent No. 2,551,252, dated May 1, 1951), filed January 21,1949, and February 15, 1946, respectively, to obtain a comparisonbetween the conventional type of wheel and brake disclosed therein andthe embodiment of this invention. By conventional construction is meantthe stationary brake member which carries the hydraulic actuators andthe juxtaposed disc which serves as the backing plate or reaction memberfor the brake. With this arrangement it is obvious that the spacesbetween the wheel sides and the brake members are wasted and only serveto increase the width dimension of the assembly. Further, since the sideadjacent the backing plate is usually convexed to accommodate thebacking plate, it is obvious that its thickness will necessarily begreater, as compared with a co-planar side, to withstand specifiedwheel-loadcarrying-stresses.

The present invention overcomes these deficiencies of prior artconstructions, with the above mentioned wasted spaces now beingoccupied, and the sides of the wheel kept in single planes. Furtheradvantages to be gained by this invention, are the use of fewer parts,reduction in size of the parts and the reduction in cost of production.

Other advantages Will appear obvious as further study is made of thisinvention, which if mentioned here would only serve to lengthenthedescription.

Although only one embodiment of the invention has been illustrated anddescribed various changes in the form and relative arrangements'of theparts may be made to suit requirements.

I claim:

1. An aircraft wheel and brake assembly comprising a wheel having a rimand spaced rim-supporting sides rotatably supported on an axle member,one of said sides serving as a carrief'for a brake" actuating means, and

the otherof said sides serving as a reaction member for the axialpressure of the brake, said reaction member being axially and radiallysupported on said axle member, the carrier side of the wheel having aplurality of circumferentially-spaced cylinder bores, pistons receivedin said bores, a main conduit member rotatable with said wheelcommunicating with the interiors of said cylinders, a swivel connectionadapted to transfer fluid pressure from a stationary conduit located inthe axle member to said main conduit member, a non-rotatable annulartorqueabsorbing member adapted to be removably secured to the axlemember between the sides of the wheel, one or more annular brake discscarried on the outer periphery of said torque-absorbing member andhaving axial but not rotative movement, one or more lined annular brakediscs carried by said wheel and having axial movement with respect tothe wheel, a lined annular pressure plate carried by said wheel and inoperative engagement with said pistons, a lining carried on the reactionside of the wheel, said pistons being actuable to frictionally compresssaid brake discs between said pressure plate and said last mentionedlining, and return springs carried by said one side plate between saidbores urging said pressure plate to released position.

2. An aircraft wheel and brake assembly comprising a wheel having a rimand spaced rim-supporting sides rotatably supported on an axle member,one of said sides serving as a carrier for hydraulic brake actuatingmeans, and the other of said sides being in abutment with a taperedbearing means to serve as a reaction member for the axial pressure ofthe brake, the carrier having a plurality of circumferentially-spacedcylinder bores, pistons received in said bores, a rotatable conduitcommunicating with the interiors of said bores, a non-rotatable annulartorque-absorbing member adapted to be removably secured to the axlemember between said sides, a stationary conduit located in said axlemember and having a swivelled connection with said rotatable conduit, aplurality of spaced annular brake discs carried on the outer peripheryof said torque-absorbing member having axial but not rotative movement,a plurality of lined annular brake discs carried by said wheel havingaxial movement and being interleaved with said non-rotatable brakediscs, a lined annular pressure plate carried by said Wheel incooperative relation with said pistons, and a lining supported on thereaction" side of the wheel, said pistons being actuable to frictionallycompress said brake discs between said pressure plate and said lastmentioned lining.

3. An aircraft wheel and brake assembly comprising a stationary wheelcarrier, a wheel having a rim and first and second axially spacedsubstantially flat rim-supporting sides, anti-friction bearingsrotatably supporting at least one of said sides on said wheel carrier,said bearings being inwardly inclined toward said wheel carrier wherebyoutward axial force on said sides can be taken by the wheel carrier, therotatable side of said wheel having a plurality ofcircumferentially-spaced cylinder bores, pistons received in said bores,a main conduit member rotatable with said wheel communicating with theinteriors of said cylinders, a stationary conduit located in said wheelcarrier, a swivel connection adapted to transfer fluid pressure fromsaid stationary conduit to said main conduit member, a non-rotatableannular torque-absorbing member arranged on the wheel carrier betweenthe sides of the wheel, a plurality of circumferentially spaced axiallyextending splines formed on the outer periphery of said torque-absorbingmember, one or more annular brake members engaging said splinesfor axialbut not rotative move'menfla plurality of circumferentially spacedaxially extending keys secured to said wheel between said sides andradially. outwardly from said splines, at least one annular brake membercarried by said keys for axial movement and for rotation with saidwheel, and a pressure plate rotatable with said wheel and slidablyengaging said keys, said plate being in operative engagement with saidpistons, said pistons being actuable to frictionally compress said brakediscs between said pressure plate and said second rim-supporting side.

4. An aircraft wheel and brake assembly comprising a stationarywheel-supporting means, a wheel having a rim and at least onesubstantially flat rim-supporting side, spaced anti-friction bearingsrotatably supporting the wheel, said bearings being inwardly inclinedtoward the center of the wheel whereby axial forces on said wheel may betransmitted to said wheel-supporting means, said substantially flatrim-supporting side having a plurality of circumferentially-spacedcylinder bores, pistons received in said bores, a main conduit memberrotatable with said wheel communicating with the interiors of saidcylinders, a stationary conduit located in said stationary wheelsupporting means, a swivel connection adapted to transfer fluid fromsaid stationary conduit to said rotatable conduit member, anon-rotatable annular torqueabsorbing member operatively secured to saidstationary wheel-supporting means, a plurality of circumferentiallyspaced axially extending splines formed on the outer periphery of saidtorque-absorbing member, one or more annular brake members engaging saidsplines for axial but not rotative movement, a plurality ofcircumferentially spaced axially extending keys secured to said wheelbetween the sides thereof and radially outwardly from said splines, atleast one annular brake member carried by said keys for axial movementand for rotation with said wheel, and a pressure plate rotatable withsaid wheel and slidably engaging said keys, said plate being inoperative engagement with said pistons, said pistons being actuatable tofrictionally compress said brake discs by pressure exerted against saidpressure plate.

References Cited in the file of this patent UNITED STATES PATENTS1,968,130 Criley July 31, 1934 2,055,081 Jacobs Sept. 22, 1936 2,089,733Criley Aug. 10, 1937 2,143,861 Clouse Ian. 17, 1939 2,386,220 Lawler eta1. Oct. 9, 1945 2,706,018 Du Bois Apr. 12, 1955 FOREIGN PATENTS 551,993Germany June 8, 1932

